In your current code, you save the GState of the current context, configure it to draw a shadow .. and the restore it to what it was before you configured it to draw a shadow. Then, finally, you invoke the superclass's implementation of drawRect:

gistfile1.txt

In your current code, you save the GState of the current context, configure it to draw a shadow .. and the restore it to what it was before you configured it to draw a shadow. Then, finally, you invoke the superclass's implementation of drawRect: .

Any drawing that should be affected by the shadow setting needs to happen after

CGContextSetShadow(currentContext, CGSizeMake(-15, 20), 5);
but before

CGContextRestoreGState(currentContext);
So if you want the superclass's drawRect: to be 'wrapped' in a shadow, then how about if you rearrange your code like this?

- (void)drawRect:(CGRect)rect {
    CGContextRef currentContext = UIGraphicsGetCurrentContext();
    CGContextSaveGState(currentContext);
    CGContextSetShadow(currentContext, CGSizeMake(-15, 20), 5);
    [super drawRect: rect];
    CGContextRestoreGState(currentContext);
}

gistfile2.txt

Probably the easiest way is to create a shadow, but use a light color instead of a dark one. Shadow details can be found here: How do I draw a shadow under a UIView? and here.

Something like this should get the ball rolling:

- (void)drawRect:(CGRect)rect
{
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSaveGState(context);
    CGContextSetShadowWithColor(context, CGSizeMake(0, 0), 10,
                                [UIColor whiteColor].CGColor);
    [super drawRect:rect];
    CGContextRestoreGState(context);
}
Update: I just tried this out. You will have to use this code on the superview of the glowing view for it to work properly.